Nulaxy KM18 Plus Bluetooth FM Transmitter User Manual

1. Introduction

The Nulaxy KM18 Plus is an advanced Bluetooth FM Transmitter designed to enhance your in-car audio experience and provide convenient hands-free communication. This device allows you to stream music from your smartphone, make and receive calls safely, and charge your devices, all through your car's FM radio system. Its upgraded features, including an ON/OFF button and a clear LCD display, ensure ease of use and optimal performance.

Figure 1: Nulaxy KM18 Plus Bluetooth FM Transmitter

2. Product Features

• Upgraded ON/OFF Button: The KM18 Plus features a dedicated power button, allowing you to easily turn the device on or off without unplugging it, preventing battery drain in some car models.


Figure 2: Dedicated ON/OFF Button for convenience.

• Multiple Audio Playback Options: Enjoy your favorite audio via Bluetooth, microSD Card, or Aux Cable connection.


Figure 3: Supports Hi-Fi music for a lossless audio experience.

• Advanced Noise Reduction: Built-in noise reduction technology ensures crystal clear sound quality for both music and calls.
• Large 1.44-inch LCD Display: Clearly view phone calls, music information, and car battery voltage at a glance, designed for minimal distraction while driving.


Figure 4: The large LCD screen provides essential information.

• Hands-Free Calling: Answer, reject, or redial calls with a single button press, ensuring safer driving.


Figure 5: Bluetooth 5.0 for stable hands-free calls.

• USB Fast Charging (5V/2.1A): Equipped with a USB port to quickly charge your electronic devices.


Figure 6: Integrated USB port for convenient device charging.

• Voltmeter Function: Monitor your car battery's voltage to ensure it's within a safe operating range.
• Flexible Gooseneck Design: Allows for easy adjustment of the device's angle for optimal viewing and accessibility.

3. Getting Started (Setup)

1. Insert into Car Cigarette Lighter: Plug the Nulaxy KM18 Plus firmly into your car's 12V cigarette lighter socket. The device will automatically power on and its display will light up.
2. Find a Vacant FM Frequency: Tune your car's FM radio to a vacant or non-interfered frequency. This is crucial for minimizing static noise and achieving the best audio quality. Frequencies at the lower end of the FM band (e.g., 88.1 MHz) are often less congested.
3. Sync Nulaxy Device to FM Frequency: On the Nulaxy KM18 Plus, press the 'CH+' or 'CH-' buttons to adjust its FM frequency to match the vacant frequency you selected on your car radio.
4. Pair with Your Phone via Bluetooth:
   • Enable Bluetooth on your smartphone.
   • Search for available Bluetooth devices.
   • Select 'KM18 Plus' from the list to pair. Once paired, the device will confirm the connection on its display.
5. Adjust Volume: For optimal audio quality, set the volume on your phone to maximum. Then, adjust the volume using your car stereo's controls. It is generally not recommended to set your car speaker volume to maximum, as this can introduce noise.

Video 1: Short demonstration of the Nulaxy KM18 Plus FM Transmitter's features and setup.

4. Operating Instructions

4.1 Music Playback

• Bluetooth Streaming: Once paired, music from your phone will automatically stream through the KM18 Plus to your car's FM radio. Use your phone or the KM18 Plus's 'Previous/Next' buttons to control tracks.
• microSD Card Playback: Insert a microSD card (up to 32GB, MP3/WMA/WMV formats supported) into the designated slot. The device will automatically detect and play music from the card.
• Auxiliary Input: Connect your audio device to the KM18 Plus using a 3.5mm Aux cable. The device will switch to Aux mode for playback.

4.2 Hands-Free Calling

• Answering Calls: When a call comes in, press the multi-function button (usually the central knob) once to answer.
• Rejecting Calls: Press and hold the multi-function button to reject an incoming call.
• Ending Calls: During a call, press the multi-function button once to hang up.
• Redialing: Double-press the multi-function button to redial the last number.
• Voice Assistant: Press and hold the multi-function button to activate your phone's voice assistant (Siri, Google Assistant) for voice commands.

4.3 Voltmeter Function

The KM18 Plus displays your car battery's voltage on its screen. This feature helps you monitor your battery's health:

• 14.8V to 13.4V: Normal voltage when your car is on and running.
• 12.8V to 12.2V: Normal voltage when your car is parked and powered off.
• Below 12V: Indicates a low battery. Consider changing the battery as soon as possible.

5. Care and Maintenance

• Keep the device clean by wiping it with a soft, dry cloth.
• Avoid exposing the device to extreme temperatures, direct sunlight, or high humidity.
• Do not disassemble the device; this will void the warranty and may cause damage.
• Ensure the device is securely plugged into the cigarette lighter socket to prevent accidental dislodgement.

6. Troubleshooting

• Static Noise/Poor Audio Quality:
  • Ensure your Nulaxy device and car radio are tuned to a truly vacant FM frequency. Avoid frequencies used by strong local radio stations.
  • Increase the volume on your phone to maximum before adjusting the car stereo volume.
  • If static persists, try a different vacant FM frequency.
  • Consider using the Aux cable connection if your car stereo has an Aux input, as this bypasses FM transmission and can provide clearer sound.
• Bluetooth Disconnection:
  • Ensure the device is powered on and within range of your phone.
  • Turn off and on both the Nulaxy device and your phone's Bluetooth, then attempt to re-pair.
  • Forget the device in your phone's Bluetooth settings and re-pair from scratch.
• Device Not Powering On:
  • Check if the car's cigarette lighter socket is receiving power (test with another device if possible).
  • Ensure the KM18 Plus is fully inserted into the socket.
  • Verify the car battery voltage using the device's voltmeter function once it powers on.

7. Specifications

8. Safety Information

Always ensure the device is securely mounted and within reach while driving. Do not operate the device while the vehicle is in motion unless it is safely mounted and easily accessible. Keep the device away from heat sources and avoid exposing it to extreme temperatures or humidity. In case of an accident or impact, immediately turn off the device and follow the manufacturer's instructions for safe disposal.

9. Warranty and Support

Nulaxy offers an 18-month warranty for the KM18 Plus, typically activated upon product registration. For any technical assistance, troubleshooting beyond this manual, or warranty claims, please contact Nulaxy customer support through their official website or the retailer where the product was purchased.